A free program for Android, by Best zipper lock screens.

This app is all about the customization of your lock screen. It gives you the option to change its background, add different themes, change the color of the icons and even add some widgets to it. 

This app is very easy to use. Just click the button to activate the app. The next thing you need to do is start pulling the zipper to the right to unlock the phone. It has a preview option to make it easy for you to see all the changes you made. This makes it easy to use the app because you don’t have to make a change then exit, see if you like it and come back to settings.